Rainbow Electronics MAX14528 User Manual
General Description
The MAX14527/MAX14528 overvoltage protection
devices feature a low 100mΩ (typ) RONinternal FET
and protect low-voltage systems against voltage faults
up to +28V. When the input voltage exceeds the overvoltage threshold, the internal FET is turned off to prevent damage to the protected components.
The overvoltage protection threshold can be adjusted
with optional external resistors to any voltage between
4V and 8V. With the OVLO input set below the external
OVLO select voltage, the MAX14527/MAX14528 automatically choose the internal ±2.5% accurate trip
thresholds. The internal overvoltage thresholds (OVLO)
are preset to 5.75V typical (MAX14527) or 6.76V typical
(MAX14528). The MAX14527/MAX14528 are also
protected against overcurrent events with an internal
thermal shutdown.
The MAX14527/MAX14528 are offered in a small, 8-pin
TDFN-EP package and operate over the -40°C to
+85°C extended temperature range.
Applications
Cell Phones
Media Players
PDAs and Palmtop Devices
Features
♦ Input Voltage Protection Up to +28V
♦ Preset Internal ±2.5% Accurate OVLO Thresholds
5.75V (MAX14527)
6.76V (MAX14528)
♦ Adjustable Overvoltage Protection Trip Level
♦ Integrated 100mΩ (typ) n-Channel MOSFET
Switch
♦ Soft-Start to Minimize In-Rush Current
♦ Automatic Overvoltage Protection Trip-Level
Selection
♦ Internal 15ms Startup Delay
♦ Thermal Shutdown Protection
♦ 8-Pin TDFN (2mm x 2mm) Package
♦ -40°C to +85°C Operating Temperature Range
MAX14527/MAX14528
Adjustable Overvoltage Protector
with High Accuracy
________________________________________________________________
Maxim Integrated Products
1
19-4357; Rev 0; 10/08
Ordering Information
PART
TOP
OVLO
(V)
MAX14527ETA+T
8 TDFN-EP* ACR 5.75
MAX14528ETA+T
8 TDFN-EP* ACS 6.76
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim's website at www.maxim-ic.com.
Note: Devices are specified over the -40°C to +85°C tempera-
ture range.
+
Denotes a lead-free/RoHS-compliant package.
T = Tape and reel.
*
EP = Exposed pad.
Typical Application Circuit
Pin Configuration appears at end of data sheet.
PIN-PACKAGE
MARK
USB
CONNECTOR
*R1 AND R2 ARE REQUIRED ONLY FOR ADJUSTABLE OVLO; OTHERWISE, CONNECT OVLO TO GND.
VBUS
1µF
IN
IN
R1
*
R2
MAX14527
MAX14528
OVLO
OUT
OUT
GND
CHARGER
INPUT
PMIC
MAX14527/MAX14528
Adjustable Overvoltage Protector
with High Accuracy
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
(All voltages referenced to GND.)
IN ............................................................................-0.3V to +30V
OUT .............................................................-0.3V to (V
IN
+ 0.3V)
OVLO........................................................................-0.3V to +6V
Continuous IN Current .............................................................1A
Peak IN Current (Note 1)..........................................................5A
Continuous OVLO Current ...................................................50µA
Continuous Power Dissipation (T
A
= +70°C)
8-Pin TDFN (derate 11.9mW/°C above +70°C) ...........954mW
Package Junction-to-Ambient Thermal Resistance (θ
JA
)
(Note 2) .....................................................................83.9°C/W
Package Junction-to-Case Thermal Resistance (θ
JC
)
(Note 2) ........................................................................37°C/W
Operating Temperature Range ...........................-40°C to +85°C
Junction Temperature......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering) .........................................+300°C
ELECTRICAL CHARACTERISTICS
(VIN= +2.2V to +28V, TA= -40°C to +85°C, unless otherwise noted. Typical values are at VIN= +5.0V and TA= +25°C.) (Note 3)
PARAMETER SYMBOL CONDITIONS
UNITS
Input Voltage Range V
IN
2.2 28 V
Input Supply Current I
IN
VIN < OVLO 80
µA
MAX14527 5.6
5.9
VIN rising
MAX14528
7
MAX14527
IN Overvoltage Trip Level V
IN_OVLO
VIN falling
MAX14528 6.5
V
IN Overvoltage Lockout Hysteresis
1%
OVLO Set Threshold
1.2
V
Adjustable OVLO Threshold Range
48V
External OVLO Select Threshold
0.5 V
Switch On-Resistance R
ON
mΩ
OVLO Clamp I
CLAMP
= 10µA 3
5.5 V
OUT Capacitor C
OUT
µF
OVLO Input Leakage Current I
OVLO
V
OVLO_THRESH
= 1.245V
nA
Thermal Shutdown
°C
Thermal Shutdown Hysteresis 20 °C
TIMING CHARACTERISTICS (Figure 1)
Debounce Time t
INDBC
Time from 2.2V < VIN < V
IN_OVLO
to
V
OUT
= 10% of V
IN
15 ms
2.2V < VIN < V
IN_OVLO
, R
LOAD
= 100Ω,
C
LOAD
= 100µF; V
OUT
from 10% to
90% of V
IN
0.7
Switch Turn-On Time t
ON
2.2V < VIN < V
IN_OVLO
, R
LOAD
= 100Ω,
C
LOAD
= 1mF; V
OUT
from 10% to 90%
of V
IN
1.4
ms
Switch Turn-Off Time t
OFF
VIN > V
OVLO_THRESH
to V
OUT
= 80% of
V
IN_OVLO
; R
LOAD
= 1kΩ, VIN rising at
2V/100ns
1.3 3.5 µs
Note 1: Limited by thermal shutdown.
Note 2: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer
board. For detailed information on package thermal considerations, refer to www.maxim-ic.com/thermal-tutorial
.
Note 3: All specifications are 100% production tested at T
A
= +25°C, unless otherwise noted. Specifications are over -40°C to +85°C
and are guaranteed by design.
MIN TYP MAX
5.75
6.55 6.765
5.54 5.84
V
IN_OVLO_HYS
V
OVLO_THRESH
V
OVLO_SELECT
1.245 1.29
0.15 0.33
100 200
4.56
-100 +100
150
160
6.95
1000
MAX14527/MAX14528
Adjustable Overvoltage Protector
with High Accuracy
_______________________________________________________________________________________ 3
Timing Diagram
90%
10%
90%
10%
t
INDBC
t
INDBC
t
ON
t
OFF
t
ON
IN
OVLO
2.2V
OUT
NOTE: WAVEFORMS ARE NOT TO SCALE.
80% V
IN_OVLO
V
IN_OVLO
Figure 1. Timing Characteristics
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